1. Field of Invention
The present invention generally relates to an articulatable positioning device, and more particularly to a hand grip device for aiding a person using an ambulatory assistance device. Still more particularly, the present invention relates to an adjustable hand grip device that is intended to be mounted on at least one of the arms of an ambulatory assistance device such as a wheelchair, a walker and the like to aid the person being assisted.
The present invention was developed to facilitate the needs of physically disabled persons who require articulate positioning of hand grips to conform with their upper extremity limitations. The hand grip is adjustable through a wide range of articulatable motion and then locked in a position which is comfortable and easily reached by the person being assisted. For example, the articulatable hand grip device of the present invention is adjustable into a wide range of positions which are easily accessible and comfortable for aiding a person attempting to get into and out of a wheelchair or attempting to reposition them self once they are seated. A preferred form of the hand grip device includes a mounting means having split clamping members which are joined about a cylindrical support structure such as the arm of a wheelchair to mount the hand grip to the chair. Preferably, the clamping members each have at least one matched arced clamping surface so that the mounting means provided a wide area clamping contact on the arm of the wheelchair.
The articulatable positioning device of the present invention is also applicable to mount many other accessories for wheelchairs, walkers and other ambulatory aids, or any other application utilizing tubing as a structural support wherein particular positioning of an accessory in a comfortable and convenient location is required while maintaining stability and rigidity. In that case, the hand grip is replaced by a tool interface. The tools could be trays, switch mounts, fishings pole holders and umbrella holders, and the like.
2. Prior Art
A number of mounting systems and hand grip devices have been constructed for conventional walkers and wheelchairs to accommodate physically disabled individuals. Of particular note is U.S. Pat. No. 5,284,313 to Hallgren which relates to an adjustable mounting system comprised of an adjustable arm capable of a wide range of motion including a telescopic feature to extend the length of the arm and a supporting clamp mountable on a tubular support structure, such as a wheelchair arm. The supporting clamp has an upper jaw with a U-shaped recess and a lower jaw having a threaded shaft with a flattened contact area to capture the tubular structure of the wheelchair or other rigid support structure therebetween. The problem is that the curved surface of the U-shaped recess in conjunction with the threaded shaft is inadequate to securely mount the Hallgren mounting system to the tubular support, in large part due to the line contact provided by the threaded shaft. Also, the curved recess will only fit one size of tubular support.
The clamping recess of the present invention accepts a plurality of different sized tubing by providing the split-collar clamps with a plurality of matching curved surfaces for contacting various diameter tubes. This construction provides a more stable mounting structure by distributing the clamping pressure to an area on the tube rather than concentrating it on a plurality of line contacts or a curved surface and opposed line contact. In addition, the mounting device of the present invention precludes the need for different sized split clamps to accommodate different sized tubular supports.
Also, the present articulatable positioning device has a wider range of movement than the mounting system described by Hallgren. Thus, while the Hallgren patent provides a system for holding a device in a particular position by use of an adjustable arm and mounting apparatus, it does not provide the stability and adaptability available in the present invention.